OZNN insulating cover for LV transformer clamps – M12 / M20 / M30
Cover included in the certificate
The OZNN insulating cover is listed as additional equipment in Certificate of Conformity No. Z/12/004/26 for TOC-1 M12 /U and /N clamps. The certificate was issued by SEP – Quality Testing Office (BBJ), a certification body accredited by PCA (No. AC 012).
Three problems you will not have
Birds and rodents
Bare clamp brass is the most common short-circuit point in a substation – a bird landing on the bushings, a marten on the cover. The cover encloses the metal in rubber; only the cable outlet remains.
Accidental touch
A live LV clamp sits at hand height. The insulating cover reduces the risk of touching a live part during work in the substation and around an enclosed transformer.
Fire and weather
Special flame-retardant rubber – does not sustain burning. A material made for outdoor service on the transformer cover, all year round.
A cover in the size of the clamp
| Cover | Clamp thread | Fits clamps | Transformer rating |
|---|---|---|---|
| OZNN M12 | M12 | TOC-1 DP 5100 / 5100NTOC-2 DP 6100 / 6100NMK 1 DP 7100 | ≤ 160 kVA |
| OZNN M20 | M20 | TOC-1 DP 5200 / 5200NTOC-2 DP 6200 / 6200NMK 1 DP 7200 | 250 / 400 kVA |
| OZNN M30 | M30 | TOC-1 DP 5300 / 5300NTOC-2 DP 6300 / 6300NMK 1 DP 7300 | 630 kVA |
Set per transformer: 4 pcs (3 phases + N). Cover size = clamp thread, and the thread = the transformer LV bushing stud. When ordering clamps with covers, just tell us the transformer rating – we match the rest.
The OZNN cover up close
Clamps it fits
TOC-1 clamp
Horizontal, with an offset foot – our standard for MarkoEco2.
TOC-2 clamp
Compact, for closely spaced bushings – the same connectivity.
OZNN cover
Ordered separately or as a set with clamps and transformer.
A cover from the transformer maker
Transformer + accessories
We match clamps and covers to our MarkoEco2 transformers; they fit any LV bushing with an M12–M30 stud.
Flame-retardant rubber
A special compound that does not sustain burning – for outdoor service on the transformer cover.
A safer substation
A covered clamp means fewer bird and rodent short circuits and less risk of touching live parts.
From stock in Poland
Clamps and covers ship from our warehouse – separately or together with the transformer.
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